blockbuster (n.) Look up blockbuster at Dictionary.com
also block-buster, big bomb (4,000 pounds or larger, according to some sources), 1942, from block (n.) in the "built-up city square" sense. Entertainment sense is attested from 1957. U.S. sense of "real estate broker who sells a house to a black family on an all-white neighborhood," thus sparking an exodus, is from 1955.